liquid foundation help?

No powder is optional. I rarely wear powder because it tends to look cakey. It sounds like maybe your not blending your foundation well enough &/or applying it evenly. Be sure to apply under your jaw line and cover your ears to. Just blend, blend, blend! You can use your fingers, a sponge or a foundation brush to apply. You may try a sponge (I find it applies better, personally)

Double check you have the right shade or maybe even try a different brand. I just bought a cheap foundation (LA colors) just to wear when I just need some coverage and don't want to use my good make-up. & dummy me bought a shade too dark and it comes out soooo blotchy, spotty and uneven.

Check youtube if needed for tips or tutorials on application.

You don't have to wear powder over you foundation if you don't want to. I don't. Use a clean makeup sponge every tiem you apply. Make sure you're not using too much or not enough. Go over your face several times with a clean makeup sponge after applying the foundation to make sure it is blended well.

how are you applying your foundation? that's a reason it could look spotty. i would not recommend using your hands to apply foundation, unless you're using a tinted moisturizer. you don't have to wear powder to make it not look spotty, just make sure you're applying it correctly and have a good foundation.

you probab;y sould, it clears up any unevenness in the skin. liquid foundation makes the skin look really smooth, powder afterwards gives it a more natural glow, so if i were u i would use powder.

use only powder is enougth

depends on how your using it go on youtube and they can teach you